Based on the time when the poem “The Second Coming” was written, Images of a “blood-dimmed tide” and of drowned innocence in lines 5–6 were probably affected by the events of World War I (C).
World War I took place from July 28, 1914 to November 11, 1918. The poem, "The Second Coming," was written by W.B. Yeats in 1919. Therefore, it is most likely that the references to war were referencing World War I that had ended just shortly before the poem was written.